A common computer peripheral input device includes a mouse, a keyboard, a trackball, and the like. The keyboard may be used to directly type words and symbols into a computer. Therefore, keyboards attract much attention of users and input device manufacturers. A subject matter of this application is a keyboard.
Referring to FIG. 1, FIG. 1 is a schematic diagram of an appearance structure of a conventional keyboard. A plurality of keys 10 and 10′ is provided on a surface of the conventional keyboard 1. The keys 10 are classified as keys with common sizes, and the keys 10′ are classified as keys with relatively large sizes. Lengths of the keys 10 are slightly greater than widths thereof, and lengths L1 of the keys 10′ are far greater than widths W1 thereof. The plurality of keys 10 and 10′ is pressed by a user by using fingers, so that a corresponding signal is generated and is sent to a computer, and accordingly, the computer executes functions of the pressed keys. Generally, by pressing the keys 10 and 10′, symbols such as English letters, and digits may be entered, or various functions (for example, F1 to F12, or delete) may be executed. The conventional keyboard 1 is a keyboard for use in a notebook computer.
An internal structure of the conventional keyboard is described in the following. Referring to both FIG. 2 and FIG. 3, FIG. 2 is a schematic exploded view of a structure of a conventional keyboard, and FIG. 3 is a schematic structural diagram of a keycap of a conventional keyboard from another viewing angle. The conventional keyboard 1 includes a plurality of keys 10 and 10′, a base plate 11, and a thin film switch circuit 12, and a plurality of key switches 121 corresponding to the plurality of keys 10 and 10′ is provided on the thin film switch circuit 12. An example of a key 10′ with a relatively large width is used for description herein. The key 10′ includes a keycap 101, a plurality of scissors-type connecting elements 102, and a rubber elastomer 103. The scissors-type connecting elements 102 are connected to both the keycap 101 and the base plate 11 and each include a first frame 1021 and a second frame 1022. The second frame 1022 is connected to the first frame 1021 by using a shaft, so that the first frame 1021 and the second frame 1022 can swing relative to each other. In addition, the rubber elastomer 103 is disposed between the keycap 101 and the base plate 11.
The base plate 11 includes a plurality of first base plate hooks 111, and the plurality of first base plate hooks 111 may be connected to the first frames 1021 and the second frames 1022. On the other hand, the keycap 101 includes a plurality of first hooks 1011, and the plurality of first hooks 1011 is disposed on an inner surface of the keycap 101 and may be connected to the first frames 1021 and the second frames 1022. Therefore, the keycap 101 is movably fastened on the base plate 11.
When a user presses a keycap 101 of any key 10′, the keycap 101 moves downwards relative to the base plate 11, so that first frames 1021 and second frames 1022 of scissors-type connecting elements 102 change from an opened state to a superimposed state, and the keycap 101 moving downwards pushes a rubber elastomer 103. Therefore, the rubber elastomer 103 is abutted and deforms, and triggers a corresponding key switch 121, so that the thin film switch circuit 12 generates a corresponding key signal. When the user no longer presses the keys 10 and 10′, the keycap 101 moves upwards relative to the base plate 11 due to an elastic force generated when the rubber elastomer 103 recovers from a deforming state. In this case, the first frames 1021 and the second frames 1022 change from the superimposed state to the opened state, and the keycap 101 recovers to a location at which the keycap 101 is not pressed.
In the conventional keyboard 1, structures of some keys 10′ whose lengths L1 are far greater than widths W1 are different from those of keys 10 because the keycaps 101 of the key 10′ have relatively large lengths L1. Therefore, in a process in which the user presses the key 10′, the keycap 101 thereof easily shakes, affecting operation smoothness of the key 10′ and even affecting pressing feelings of the user. Therefore, the key 10′ is further provided with a special mechanism to improve the operation smoothness thereof. The key 10′ further includes a plurality of balance bars 104, and each of the balance bars 104 includes a connecting rod portion 1041 and two hook portions 1042. The two hook portions 1042 are respectively located at two ends of the balance bar 104.
In addition, the base plate 11 further includes a plurality of second base plate hooks 112, and the second base plate hook 112 includes a plurality of hook holes 1121. Each hook hole 1121 corresponds to one hook portion 1042 and is used for the corresponding hook portion 1042 to penetrate, so that the balance bar 104 is fastened on the base plate 11. On the other hand, the keycap 101 further includes a plurality of second hooks 1012, and the plurality of second hooks 1012 is disposed on the inner surface of the keycap 101 and is arranged in a row. The plurality of second hooks 1012 corresponds to one connecting rod portion 1041, so that the connecting rod portion 1041 is fastened in openings 1013 of the plurality of second hooks 1012. Each opening 1013 has a same width W2, and each opening 1013 has a round shape. The balance bar 104 may be fastened on the keycap 101 and the base plate 11 respectively by using the plurality of second base plate hooks 112 and the plurality of second hooks 1012. By setting the plurality of balance bars 104, the key 10′ can be kept balanced so as not to incline in a process of moving upwards or downwards relative to the base plate 11, and the structural strength of the keycap 101 can also be enhanced.
However, in a process of manufacturing the keycap 101, the keycap 101 inevitably has a manufacturing tolerance; therefore, the plurality of openings 1013 of the plurality of second hooks 1012 arranged in a row cannot be accurately located in a same axial direction. Consequently, it is difficult to assemble the balance bar 104 into the plurality of second hooks 1012. Even if the balance bar 104 and the plurality of second hooks 1012 may be barely combined due to elastic materials of the balance bar 104 and the plurality of second hooks 1012, because in a process of pressing the keycap 101, the connecting rod portion 1041 excessively extrudes the plurality of second hooks 1012, the balance bar 104 unsmoothly rotates in the plurality of openings 1013 of the plurality of second hooks 1012, affecting pressing feelings when the user presses the keycap 101. In extreme cases, the second hooks 1012 would even be broken due to rotation of the balance bar 104.
Therefore, a keyboard capable of improving pressing feelings is needed.